The family is a remarkably significant social unit. It is defined a group of individuals, related by blood, marriage, adoption or cohabitation (AIFS, 2001). In all known societies the family has the function of regulating sexual behaviour and reproduction, of socialization, of protecting children and the elderly, and of providing its members with emotional support, health and well being
Over the last few decades, family formation patterns have changed considerably. Contemporary family sociology has identified that family practices, too, are also changing rapidly. Massive demographic change has signaled significant changes in family-form with family-households now being considerably smaller in size. Moreover, there is evidence that the norms governing family life are also undergoing a major over haul.
Polygynous marriages, which involve one man and a number of women. In North America this was practiced extensively among Mormons, but was largely phased out during the 19th century. Today, it appears to be confined to small Fundamentalist Mormon groups which have been excommunicated by the main Mormon church.
Homosexual unions of two men or two women. These can be registered as civil unions in the state of Vermont. The couple obtains all of the privileges and responsibilities that the State of Vermont gives to heterosexual married couples. The couple can register as a domestic partnership in the province of Nova Scotia, Canada. The couple receives all of the privileges and responsibility of married couples, except for the right to adopt. Homosexual marriages of two men and two women: These are currently available only to residents in the Netherlands. In that state, no differentiation is made between opposite-sex and same-sex couples who wish to marry.